implement hosting domain creation

- implement domains.views.CreateHostingDomain
- define new URL create_hosting_domain in domains.urls
- add domains app URLs to gnuviechadmin.urls
- add templates domains/base.html and domains/hostingdomain_create.html
- link from hostingpackage detail page to domain creation view

gnuviechadmin/gnuviechadmin/urls.py

@@ -10,6 +10,7 @@ urlpatterns = patterns(
     '',
     url(r'', include('dashboard.urls')),
     url(r'^accounts/', include('allauth.urls')),
+    url(r'^domains/', include('domains.urls')),
     url(r'^hosting/', include('hostingpackages.urls')),
     url(r'^osuser/', include('osusers.urls')),
     url(r'^admin/', include(admin.site.urls)),